Whoever can first figure out how I have hidden the 0.25 BTC gets it. The 0.25 BTC are waiting for you at 1AJ3vE2NNYW2Jzv3fLwyjKF1LYbZ65Ez64 (just sent it now).

Companies claiming they got hacked and lost your coins sounds like fraud so perfect it could be called fashionable. I never believe them. If I ever experience the misfortune of a real intrusion, I declare I have been honest about the way I have managed the keys in Casascius Coins. I maintain no ability to recover or reproduce the keys, not even under limitless duress or total intrusion. Remember that trusting strangers with your coins without any recourse is, as a matter of principle, not a best practice. Don't keep coins online. Use paper wallets instead.

Companies claiming they got hacked and lost your coins sounds like fraud so perfect it could be called fashionable. I never believe them. If I ever experience the misfortune of a real intrusion, I declare I have been honest about the way I have managed the keys in Casascius Coins. I maintain no ability to recover or reproduce the keys, not even under limitless duress or total intrusion. Remember that trusting strangers with your coins without any recourse is, as a matter of principle, not a best practice. Don't keep coins online. Use paper wallets instead.

LOL. But I mean 0.25 BTC you can actually spend, not the occurrence of the substring "0.25 BTC" in the string.

Well if you sent it to me I could spend it, couldn't I?

If you find it you will be able to send it to yourself.

Companies claiming they got hacked and lost your coins sounds like fraud so perfect it could be called fashionable. I never believe them. If I ever experience the misfortune of a real intrusion, I declare I have been honest about the way I have managed the keys in Casascius Coins. I maintain no ability to recover or reproduce the keys, not even under limitless duress or total intrusion. Remember that trusting strangers with your coins without any recourse is, as a matter of principle, not a best practice. Don't keep coins online. Use paper wallets instead.

Given that it is a specific address, it would indicate that the solution will eventually resolve into either a wallet.dat or a private key (and given casascius's service, I'd guess that the solution is a private key) and isn't the login to an online wallet, as those can't guarantee sending from a specific address.

The string is very short and generic, and so it seems a little unlikely that the private key somehow is encoded into it. A private key is 256 bits and the string (assuming casascius is only looking for a-z,A-Z,0-9, period, comma, space, even including the quotes, gives a total of 66 symbols, or ~6 bits per character) has a total of 324 bits... That really doesn't include enough to hide it stego-style in such a pretty sentence.

Given that this is ruled out, its probably more likely to be a logic or lateral puzzle. plain site... site, website... somewhere on his website, view source, ctrl-f, plain.htm, plain.html.